Title: Deep Synoptic Array science: a 50 Mpc fast radio burst constrains the mass of the Milky Way circumgalactic medium Show Chinese title

Title: 深空全景阵列科学：50 Mpc快速射电暴限制银河系晕状介质的质量

Abstract: We present the Deep Synoptic Array (DSA-110) discovery and interferometric localization of the so far non-repeating FRB 20220319D. The FRB originates in a young, rapidly star-forming barred spiral galaxy, IRAS 02044$+$7048, at just 50 Mpc. Although the NE2001 and YMW16 models for the Galactic interstellar-medium (ISM) contribution to the DM of FRB 20220319D exceed its total observed DM, we show that uncertainties in these models accommodate an extragalactic origin for the burst. We derive a conservative upper limit on the DM contributed by the circumgalactic medium (CGM) of the Milky Way: the limit is either 28.7 pc cm$^{-3}$ and 47.3 pc cm$^{-3}$, depending on which of two pulsars nearby on the sky to FRB 20220319D is used to estimate the ISM DM. These limits both imply that the total Galactic CGM mass is $<10^{11}M_{\odot}$, and that the baryonic mass of the Milky Way is $\lesssim60\%$ of the cosmological average given the total halo mass. More stringent albeit less conservative constraints are possible when the DMs of pulsars in the distant globular cluster M53 are additionally considered. Although our constraints are sensitive to possible anisotropy in the CGM and to the assumed form of the radial-density profile, they are not subject to uncertainties in the chemical and thermal properties of the CGM. Our results strongly support scenarios commonly predicted by galaxy-formation simulations wherein feedback processes expel baryonic matter from the halos of galaxies like the Milky Way. Show Chinese abstract

Abstract: 我们介绍了深度综述阵列（DSA-110）对迄今为止非重复的快速射电暴20220319D的发现和干涉定位。 该快速射电暴起源于一个年轻的、快速恒星形成的棒旋星系IRAS 02044$+$7048，距离仅50兆帕秒。 尽管NE2001和YMW16模型对银河系星际介质（ISM）对快速射电暴20220319D的DM贡献超过了其总观测DM，但我们表明这些模型中的不确定性可以容纳爆发的河外起源。 我们推导出银河系星系晕介质（CGM）对DM的保守上限：该上限为28.7 pc cm$^{-3}$和47.3 pc cm$^{-3}$，具体取决于使用哪颗在天空中靠近快速射电暴20220319D的脉冲星来估计ISM DM。 这些限制都意味着银河系的总银河系CGM质量是$<10^{11}M_{\odot}$，并且根据总晕质量，银河系的重子质量是宇宙平均值的$\lesssim60\%$。 当进一步考虑遥远球状星团M53中脉冲星的DM时，可以得到更严格但不太保守的约束。 尽管我们的约束对CGM中的可能各向异性以及径向密度剖面的形式敏感，但它们不受CGM的化学和热性质不确定性的制约。 我们的结果强烈支持由星系形成模拟通常预测的情景，其中反馈过程将重子物质从类似银河系的星系晕中驱逐出去。